1. Field of the Invention:
The present invention relates, in general, to the method of forming beaded transfixion wires or pins for orthopedic uses.
2. Information Disclosure Statement:
Heretofore, beaded transfixion wires or pins have been formed from two parts, i.e., a wire and a bead. The prior art methods of forming the beaded transfixion wire or pin included the steps of providing a hole in the bead and fitting the bead on the wire by extending the wire through the hole. The next step was then to fix the bead onto the wire by silver soldering, welding, crimping or the like. The final steps were to provide a drill point on one end of the beaded transfixion wire, and then to finish the product by polishing same, as for example to smooth out the soldering or welded joint between the wire and the bead.
So-called Swiss-type for sliding-headstock machines are known in the prior art and some include a tube feeder, sliding-headstock, a guide bushing having a collet, a cutting tool, and a support which the end of the stock engages to eliminate deflection. Although such machines have been known in Europe for many years and the problems in manufacturing transfixation wires or pins formed from two parts have also been known for a long time, due to the small diameter and length of such wires or pins, prior to the present invention no thought has been given to forming the wires or pins with the bead being integral with the wire or attempting to form same on such sliding-headstock machines. The following publications provide examples of such sliding-headstock machines: Tool and Manufacturing Engineers Handbook (3rd Edition), pages 5-121-5-127; Marubeni Citizen-Cincom Inc. brochure; Citizen Watch Co., LTD. catalog No. 150E, 1986; Citizen Watch Co., LTD. catalog No. 121E, 1985; Star Micronics Co., LTD. catalog RNC-16; Star Micronics Co., LTD. catalog KNC-16.20; and Star Micronics Co., LTD. catalog KNC-25/32.
Ilizarov et al U.S. Pat. No. 4,615,338 issued 10/7/86 shows one type of automatic compression-distraction apparatus with which the beaded transfixion wire of the present invention may be used.